JPH028521B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a split type transformer used in ultra-high voltage power transmission systems such as 500KV and 1000KV, and particularly relates to a through-wall conductor support device and a gas insulated arrester. This invention relates to an external connection device with an improved combination structure.

[Background technology of the invention and its problems]

With the increase in electricity demand in recent years, 500KV class ultra-super high voltage power transmission has been realized, and 1000KV class power transmission is also planned.

As is well known, the transformers installed in ultra-high voltage power generation and substations are constructed by combining multiple unit transformers to form single-phase transformers due to various transportation restrictions and increased transformer capacity. These are combined into a three-phase transformer bank.

On the other hand, as there is a strong demand for smaller installation spaces and more emphasis is placed on aesthetic appearance, the use of gas-insulated busbars to connect transformers and switchgear in power generation and substations is increasing. Furthermore, gas insulated arresters, which are more compact, are now being used instead of conventional air arresters. However, such gas-insulated arresters have a total length of up to 2 meters, so depending on the installation condition, the installation space of the entire transformer may increase, or it may cause problems during on-site assembly, expansion, or disassembly, or it may cause earthquake resistance problems. Problems arise when the reliability of the transformer and the reliability of the transformer are reduced.

[Purpose of the invention]

The present invention was made in consideration of the above-mentioned problems, and its purpose is to minimize the installation space of a gas insulated bus bar and a gas insulated arrester, and to improve earthquake resistance without impairing workability such as on-site assembly. An object of the present invention is to provide an external connection device for a transformer that can improve insulation reliability.

[Summary of the invention]

In order to achieve such an object, the present invention provides an external connection device for a transformer in which at least a high voltage side lead and an intermediate voltage side lead of the transformer are respectively connected to a conductor of a gas insulated bus bar through a through-wall conductor support device. While pulling out the high voltage side lead from the side of the transformer,
Pull out the medium-voltage side leads from the top of the transformer, connect each of them to a through-wall conductor support device arranged almost horizontally, and place the gas-insulated arrester connected to the high-voltage side line on the same horizontal plane as the high-voltage side through-wall conductor support device. A gas insulated arrester is placed on the side of the transformer in a direction orthogonal to the line and connected to the medium voltage side line.

[Embodiments of the invention]

Hereinafter, the present invention will be explained based on illustrated embodiments.

FIG. 1 is a plan view showing an external connection device for a transformer according to an embodiment of the present invention, and FIG. 2 is a front view taken along the line "A"--"A" in FIG. 1.

A plurality of unit transformers (a) and (b) each consist of a core and a winding (1) stored in a tank (2) together with an insulating medium, transported individually, and connected via a duct (3) at the site to form each unit. By connecting the windings of transformers A and B in parallel, it becomes a single-phase transformer. A duct 4 configured at right angles is connected to the side of the tank 2 on the side of one unit transformer A that does not face the other unit transformer B, and a wall consisting of a through-wall bushing arranged almost horizontally at the tip of the duct 4 A through-conductor support device 5 is installed along the longitudinal direction of the unit transformer A. The parallel-connected high-voltage side leads of unit transformers A and B are drawn out from the axial center of the windings, passed through the duct 4, and connected to one end of the through-wall conductor support device 5. A duct 6 is attached to the other end of the through-wall conductor support device 5, and a gas insulated bus bar 7 is connected to the duct 6 via a flange portion 6a. The other end of the through-wall conductor support device 5 is connected to a switchgear (not shown) via conductors in the duct 6 and the gas insulated bus bar 7. A flange portion 7a is provided on the side of the gas insulated bus bar 7, and a gas insulated arrester 8 is attached to this flange portion 7a. This gas insulated arrester 8 has an arrester element 8b in which non-linear resistor elements are laminated in a case 8a.
The entire unit is arranged on the same horizontal plane as the through-wall conductor support device 5 on the short sides of the unit transformers A and B. One end of the arrester element 8b is connected to a conductor in the gas insulated bus bar 7 and connected to the high voltage side line, and the other end of the arrester element 8b is grounded. Note that an insulating gas such as SF ₆ gas is filled inside the case 8a, the duct 6, and the gas insulated bus bar 7, but an insulating spacer may be provided on at least one of the flange portions 6a and 7a to separate the gas. .

On the other hand, a duct 9 configured at right angles is connected to the upper surface of the tank 2 of the unit transformer A, and a through-wall conductor support device 10 consisting of through-wall bushings arranged almost horizontally is connected to the top of the duct 9 at the top of the tank 2 of the unit transformer A. It is installed along the direction of the hand. The medium-voltage side leads of unit transformers A and B connected in parallel are pulled out from the axially upper part of the winding and passed through the duct 9 to the through-wall conductor support device 1.
Connected to one end of 0. A duct 11 having a flange portion 11a on the side is connected to the other end of the through-wall conductor support device 10, and a gas insulated bus bar 12 is directly connected to the flange portion 11a of the duct 11. The other end of the through-wall conductor support device 10 is connected to a conductor within this gas insulated bus bar 12 and connected to a switchgear (not shown). Note that the gas insulated bus bar 12 and the through-wall conductor support device 10 are arranged on the same horizontal plane at right angles. A flange portion 12 is provided on the lower side of the gas insulated bus bar 12.
a is provided, and a gas insulated arrester 13 is attached to this flange portion 12a. The gas insulated arrester 13 is composed of a case 13a connected to a flange portion 12a, and an arrester element 13b, which is housed in the case 13a and has non-linear resistance elements laminated. They are placed on the short sides of unit transformers A and B in the orthogonal direction. One end of the arrester element 13b is connected to a conductor within the gas insulated bus bar 12 and connected to the medium voltage side line, and the other end is grounded. In addition, inside the duct 11, gas bus bar 12 and case 13a,
Although an insulating gas such as SF ₆ gas is sealed, an insulating spacer may be provided on at least one of the flange portions 11a and 12a to separate the gas. In addition, if necessary, install a soundproof tank around unit transformers A and B.
4 may be provided.

With this configuration, the gas-insulated arresters 8 and 13 on the high-voltage side and medium-voltage side are connected to the closest position to the transformer to be protected, so not only can their functions be utilized to the maximum, but also Even though the gas insulated arresters 8 and 13 are attached, they are placed in the space to the side of the two unit transformers A and B in a direction perpendicular to the through-wall conductor support devices 5 and 10. , the installation space for the transformer does not become large. Especially when the high voltage side is 1000KV class, case 8a of duct 6 and gas insulated arrester 8
Considering that the outer diameter of the spacer is approximately 1,000 to 1,500 mm, and that the land area including the supporting material is increasing, not having to increase the size of the installation spacer has an extremely large economic effect.

In addition, the gas insulated bus bar 12 on the medium voltage side is placed above the unit transformers A and B (or above the soundproof tank 13), taking advantage of its lighter weight compared to oil-filled ducts, so that the support structure and Earthquake-resistant design does not become complicated.

Furthermore, gas insulated busbars 7 on the high pressure side and medium pressure side,
12 can be drawn out perpendicularly to the direction in which unit transformers A and B are installed in parallel, so even if an additional unit transformer is installed next to unit transformer B to increase the transformer capacity, gas insulation can be achieved. There is no need to change the arrangement of the busbars 7 and 12. Furthermore, each unit transformer (a) and (b) can be configured to have the same and simple shape, and the length of the duct 4 on the oil side, which has poorer voltage resistance than the gas side, can be shortened, resulting in high insulation reliability. Become. In addition, since the unit transformers A and B, which are heavy, can be installed first, and the gas insulated arresters 8 and 13 and the gas insulated busbars 7 and 12 can be assembled in order based on them, during on-site assembly or disassembly. workability is not impaired.

In the above embodiment, a single-phase transformer is constructed with two unit transformers A and B, but it can also be constructed with one or three or more unit transformers, and can also be constructed by penetrating a wall. The conductor support devices 5 and 10 may use through-wall spacers instead of through-wall bushings.

〔Effect of the invention〕

As explained above, according to the present invention, even though gas insulated arresters are included on the high-pressure side and medium-pressure side, the installation space can be minimized, and earthquake resistance can be achieved without impairing workability such as on-site assembly. It is possible to provide an external connection device for a transformer with high insulation reliability.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an external connection device for a transformer according to an embodiment of the present invention, and FIG. 2 is a view taken along the line "A"--"A" in FIG. 1... Contents of unit transformer, 2... Tank, 3, 4,
6, 9, 11...Duct, 5...Through-wall conductor support device on high voltage side, 7, 12...Gas insulated bus bar, 8...Gas insulated arrester on high pressure side, 10...Through wall conductor support device on medium voltage side, 13...Medium Gas-insulated arrester on the pressure side.

Claims (1)

[Claims] 1. Pull out the high-voltage side lead of the transformer from the side of the transformer tank and connect it to the conductor of the gas-insulated bus bar through a through-wall conductor support device arranged almost horizontally, and connect the medium-voltage side lead of the transformer to the top of the transformer tank. The gas-insulated arrester connected to the high-voltage line is connected to the conductor of the gas-insulated bus bar through a through-wall conductor support device that is pulled out from the wall and arranged almost horizontally, and the gas-insulated arrester connected to the high-voltage side line is placed on the same horizontal plane as the through-wall conductor support device on the high-voltage side. an external connection for a transformer, wherein the gas insulated arrester on the medium voltage side is placed on the side of the transformer in a direction orthogonal to the through-wall conductor support device on the medium voltage side. Device.